An authentication using human biometric information such as a fingerprint, a palm print, a vein pattern, an iris, a face image or a sound is used as an identification means having high reliability. In a biometric authentication technology field, it is demanded that biometric feature information of biometric information that is useful for identification is expressed by a biometric feature binary string that is expressed by a binary string of “0” and “1”. When the biometric feature information is binarized, a size of the biometric feature information is reduced, and it is possible to perform a matching with a simple distance calculation. It is possible to achieve a usage scene such as a biometric authentication with a low spec CPU such as an IC card, an ultrahigh-speed comparison of many biometric data, a cancelable biometric authentication destroying enrolled biometric data or generating a new enrolled data from the biometric data.
However, biometric information input by a user may fluctuate according to an inputting method or an environment. Therefore, a repeatability of biometric feature information extracted from identical biometric information may be degraded, and matching accuracy may be degraded.
And so, Japanese Patent Application Publication No. 5-197793 discloses that a feature point of a face image is extracted with respect to each component of the face. International Publication Pamphlet No. WO 2008/133235 discloses a method in which a biometric image is converted into a frequency component, a main component of the frequency component is used as biometric feature information, a distance calculation by performing a DP (Dynamic Programming) matching and a HMM (Hidden Markov Model) independently in a vertical direction and a horizontal direction, and a matching having a resistance against a positional shift and a distortion is achieved. International Publication Pamphlet No. WO 2009/104429 discloses a method performing a robust matching by dividing a fingerprint image into small regions including two or three ridge lines and relating small regions having a high correlation between enrolled fingerprint image and an input fingerprint image to each other in a fingerprint authentication.